35 



The parent birds began feeding their young at daybreak and 

 continued to do so until dusk, at intervals of only a few minutes 

 between each visit. The old birds did not, as a rule, go far 

 afield for the food, often procuring it from among the various 

 plants under cultivation in the garden near to their nest ; 

 sometimes they visited an adjacent orchard and occasionally 

 they disappeared entirely. On searching the plants for insects 

 in the neighbourhood of the nest I found that two kinds of 

 caterpillars were present in large numbers : the cabbages were 

 swarming with the larvae of the Cabbage Moth (Matnestra 

 brassicce), and the groundsel with the larvae of the Cinnabar 

 Moth' (Hipocrita jacobcece) ; there were the usual colonies of 

 plant lice upon rose, apple and plum ; Daddy-long-legs 

 (Tipula spp.) in the orchard ; and everywhere muscid flies of 

 many kinds, &c. 



161. By careful watching I found that the food brought in 

 to the young consisted largely of small moth larvae, chiefly 

 Noctuids, though one could occasionally detect also the long 

 slender body of a Geometer ; numbers of Crane Flies (Tipula sp.) 

 were also brought in, but the smaller insects were not deter- 

 minable. I discovered eventually that the birds often secured 

 the partly-grown larvae of the Cabbage Moth (Mamestra bras- 

 sicce) ; and although I could never be quite sure, I am under 

 the impression that they also occasionally fed their young on 

 the partly grown larvae of the Cinnabar Moth. Had they 

 brought in the fully matured larvae of this insect I could have 

 detected them quite easily, as I was often within a few paces of 

 the old birds, but I could never see the conspicuous yellow and 

 black bands so characteristic of the insect. The question could 

 have been decided with a shot-gun, but I preferred to make 

 experiments. Four days before the youngsters left their 

 nest I impaled some larvae of H. Jacobcece on the end of a thin 

 pointed stick and presented them to the young wrens. One 

 of the birds ate 5 (2, 2 and 1) with evident relish. I then 

 offered 8 more of the larvae to the other inmates of the nest, 

 and these also were readily swallowed. I then waited for 

 some minutes to satisfy myself that they were not rejected. 

 The experiment was repeated the following day with precisely 

 the same results. On the third succeeding day I offered the 

 birds 2 more of the larvae, but these were absolutely refused, 

 (4127) D 2 



